add comma in price numbers

rial.js

function addCommaByID(id) {
    var price;
    price = "";
    var field = document.getElementById(id);

    while (field.value.indexOf(',') != -1) {
        field.value = field.value.replace(',', '');
    }

    txt_field = field.value.length;
    var counter = 0;
    for (var i = txt_field - 1; i >= 0; i--) {
        price = field.value.charAt(i) + price;
        counter++;
        if (counter % 3 == 0 && i > 0) {
            price = ',' + price;
            counter = 0;
        }
    }
    field.value = price;
}

function addComma(e) {
    var price;
    price = "";
    var eventSource = e.srcElement || e.target;
    var field = document.getElementById(eventSource.id);

    while (field.value.indexOf(',') != -1) {
        field.value = field.value.replace(',', '');
    }

    txt_field = field.value.length;
    var counter = 0;
    for (var i = txt_field - 1; i >= 0; i--) {
        price = field.value.charAt(i) + price;
        counter++;
        if (counter % 3 == 0 && i > 0) {
            price = ',' + price;
            counter = 0;
        }
    }
    field.value = price;
}

$(document).ready(function () {
    commaByClass('insertComma');    
});

function commaByClass(cl) {
    
    var items = document.getElementsByClassName(cl);
    for (var j = 0; j < items.length ; j++) {
        var price;
        price = "";
        var field = items[j];
        while (field.innerHTML.indexOf(',') != -1) {
            field.innerHTML = field.innerHTML.replace(',', '');
        }

        txt_field = field.innerHTML.length;
        var counter = 0;
        for (var i = txt_field - 1; i >= 0; i--) {
            price = field.innerHTML.charAt(i) + price;
            counter++;
            if (counter % 3 == 0 && i > 0) {
                price = ',' + price;
                counter = 0;
            }
        }
        field.innerHTML = price;
    }    
}